Process for the manufacture of amorphous carbon



Patented Nov. 15 1932 UNETEE) STATES PATENr .oFFi-cE rnocnss FOR THE manuracrurui or 'AMonrHoUs cannon No Drawing. Application filed January 11, 1932, Serial noissaoss, and in, Belgium January 16,1931.

This invention relates to a process for manufacturing amorphous carbonsimilar to the carbon or lampblack known by the name carbon black of America, as is used in umerous industries.

The object ofthe invention is to carry out this manufacture starting with carbon dioxidle, and more particularly to utilize for this purpose the by-products obtained in the manufacture of pure hydrogen by the reaction of water gas upon hydrated slaked lime.

In this manufacture, as is well known, the action of the water gas upon the slaked lime brought into the form of granules or porous bodies placed in externally heated retorts re sults in the production of calcium carbonate and possibly carbonate of iron if ferric oxide was previously added to the lime employed, and it is the custom to 'treatthese by-products under the action of heat so as to regenerate the quicklime and ferrous oxide, and to derive advantage from the carbon dioxide which is liberated. According to the invention, the carbon dioxlde thus obtained,

or possibly of any other origin,'is taken as starting point for the manufacture of amorphous carbon or lampblack,and is first of all converted into a gas (CO-l-H by passing it, together with steam, through iron in a gas tight retort, so as to produce, independently of the aforesaid gas, oxide of iron capable of being utilized in the preparation of granules of lime, whereupon the gas obtained (GO +H is passed, with a fresh quantity of steam, into another gas-tight retort charged with calcium carbide, in which retort under the action of an external source of heat, the calcium carbide is decomposed,

lected separately, into quicklime and pure carbon which may be separated from the lime.

In order to make the invention better understood. an example of its application to the treatment of the by-products of the manufacture of pure hydrogen by meansof water gas will bevdescribed hereinafter.

As is known, the water gas (CO+H utilized in this manufacture must be made in of steam alone over preferably made from a ,paste lime (OaO), ferric oxide (Fe O- and water (H O). During the passage of-the water gas f I posed under the action of and to permit thecarbondioxide to be recov-' ered according to the equation:

with the liberation of hydrogen which is 001- an enclosed vessel, that is to say, in retortswliich do not allow any air to enter and which so that, by thepassage wood charcoal oricoke of any origin,the resulting gas is only composed of hydrogen (about-80%) and carbon monoxide (about 20%) This water afterwards passed in'toa second group 0 siml ilar retorts, filled with granules of lime and heated externally. The said granules are composed of are heated externally,

over the said granules-the gas is separated and converted into pure hydrogen, which is collected in a gas holder, calcium carbinate and carbonate of iron, thelatter products be- M ing formed according to the reactionz a(ooj+H2 +Fe0a+ c tou ;+H o

" CaCOgl QFeCO -l- SH The calcium carbonate carbonateofiron (FeC )are then decomheat in order to regenerate the quicklime and ferrous oxide,

, c oo;ear coi jo oiereo eecoi.

The carbon dioxid'ethus obtained is then utilized for thennanufacture of amorphous n, For this'purpose, it is passed with steam through iron in a third closed "retort.

carbon or lampbla ck;

The retort being heated to redness, a gas ous production the reactlonz 300 311 0 +41%: 2Fe 0, 3 (00 H The ferric oxide is used again'in the manufacture of the granules of lime, collected ina gas holder, is into a fourth o retort carbide (CaCZ) and heated to a afterwards sent charged with calcium provided with a steam inlet temperature of about 250 C cording to the reaction:

, 4cao+ 4rr, +11c, V V with the production of hydrogen which is (CaGOQ) "and the? 1 7' is obtained having the same composition as water gas'wlth the simultaneof ferric made according to while the gas, -12? The calcium carbide is then decomposedaccausing Water; gas

given OE and is collected in a gas holder, and the production of quicklime and amorphous carbon.

It will be remarked that steam (H O) takes part in the foregoing reaction, which steam has the advantage of facilitating the Work and the reaction, While increasing the quantity of carbon black and producing anaddi tional quantity of hydrogen.

It is then merely necessary to separate the carbon from the lime in order finally to obtain the desired product. This separation may be effected, for example, by treating the mixture With a solution of hydrochloric acid which absorbs the calcium oxide.

VV-hat'l claim is:

' 1. A process for manufacturing carbon and hydrogen, comprising the steps of CO +11 and steam to react upon calcium carbide, about 250 C. in an" air tight retort and of separating the lime,-carbon and hydrogen obtained.

2. A process for manufacturing amorphous carbon and hydrogen comprising the steps of causing carbon dioxide and steam to pass over iron in a closed retort, of causing the gas (CO+H thus obtained to react With steam upon calcium carbide during heating to about 250 C.-in anair-tight retort, and of separating the lime, carbon and hydrogen obtained.

3. A process for manufacturing amorphous carbon and hydrogen, comprising the steps of causing Water gas to react on a heated mixture of slaked' lime .and ferric oxide, of calcinating the mixture of carbonates obtained of causing the freed carbon dioxide to p ass together with steam over iron in a closed retort, f causing the gas thus obtained to react With steam upon calcium carbide during heating to about 250 C. in an air tight retort, and of separating the lime, carbon and hydrogen obtained. i

In testimony whereof I JOSEPH VITAL GHISLAINIVAN DEN DRIESSCHE.

amorphous of heating to V affix my signature. 

